Physics definitions

when light travels from a denser to a rarer medium, the angle of incidence whose angle of refraction is 90° is the critical angle

anything that causes the velocity of an object to change

of a body is a measure of how difficult it is to accelerate that body

the force that gives a mass of 1kg an acceleration of 1m/s²

a force f moves a body through displacement s in the direction of the force, the work w done is equal to fxs

the work done when a force of 1N acts for a distance of 1m in the direction of the force

the rate at which energy is converted from one form to another

the time taken for a satellite to go once around the central body

the transfer of heat by the passing of molecular vibration from molecule to molecule without any overall motion to the substance

the heat transfer through a fluid by means of circulating currents caused by heat

the transfer of heat in the form of electromagnetic waves

of a structure is the amount of energy conducted per second through 1m² of the structure when a temp. diff. of 1°C is maintained at its ends

the average amount of the suns energy falling per second perpendicularly on 1m² of the earth's atmosphere

a disturbance carrying energy through a medium without any overall motion to that medium

mechanical or electromagnetic is a disturbance that travels away from the source producing it, transferring energy to places that it passes

waves from two sources meet, new wave produced. displace. at any point of new wave is the algebraic sum of the displace. of each other own

waves from two coherent sources meet and the pattern form is an interference pattern

formed when two periodic travelling waves of same frequency and amplitude from opposite directions meet

the rate at which sound energy is passing through unit area at right angles to the direction in which the sound is travelling at that point

at a point in an electric field is the force per unit charge at that point i.e force per coulomb

ratio of charge on a conductor to its potential

when placing a charge of 1C on a conductor raises its potential by 1V

a voltage when applied to a circuit

a resistance of 1 ohm when the current through it is 1A and the p.d across it is 1V

the amount of energy used by a 1000W appliance in one hour

the region at both sides of a p-n junction that contains no free majority charge carriers, behaves like an insulator

the p.d that exists across a p-n junction caused by holes and electrons moving across the junction when it was formed

a vector. Magnitude: the force that would be felt on a 1m conductor carrying 1A at right angles to the field, direction: force on north pole

magnetic flux density is 1 tesla if a 1m conductor carries 1A and experiences a force of 1N when placed perpendicularly to the field

constant current, 2 parallel conductors, infinite length, negligible cross section, 1m apart, vacuum produce a force on each of 2x10^-7N/m

whenever the magnetic field passing through a coil changes, an emf appears in the coil

flux is 1W when the magnetic flux density is 1tesla over and area of 1m²

a device that converts mechanical energy to electrical energy

when a changing magnetic field in one coil causes an induced emf to appear in another nearby coil

when the current passing through a coil changes, the magnetic field around it changes causing an induced emf that opposes the changing curre

device used to change the value of an alternating voltage

is the giving off of electrons from the surface of a hot metal

the amount of energy gained or lost by an electron when it moves through a potential difference of one volt

is the emission of electrons from the surface of a metal by electromagnetic radiation of a suitable frequency

of a metal is the minimum energy required to remove the loosest electron from the surface of that metal

high frequency electromagnetic radiation produced when high speed electrons (cathode ray tube) strike a metal target with a high melting pt.

when light from a luminous source undergoes dispersion the resulting pattern is an emission spectrum

a fixed energy value an electron in an atom may have

fast moving helium nuclei

high-speed electron

high frequency electromagnetic radiation

the number of nuclei decaying per second

the creating of two particles from energy, a particle and its anti-particle are produced. Momentum and electric charge are conserved

a particle that has no other particles inside it or has no sub-parts to it

a particle that does not feel the strong force

does feel the strong force

elementary particles out of which baryons and mesons are made. Have a charge of ±⅓e or ±⅔e

is made up of any one quark and any one anti-quark

is made up of any three quarks

is made of any three anti-quarks